diff --git a/po/R-zh_CN.po b/po/R-zh_CN.po
index 893b189c88..54f18be2c2 100644
--- a/po/R-zh_CN.po
+++ b/po/R-zh_CN.po
@@ -1183,18 +1183,21 @@ msgid "Internal error -- empty rhsnames in dcast; please report"
 msgstr ""
 
 msgid "The melt generic in data.table has been passed a"
-msgstr ""
+msgstr "data.table 中的 melt 泛型函数被传递了"
 
 msgid ""
 ", but data.table::melt currently only has a method for data.tables. Please "
 "confirm your input is a data.table, with setDT("
-msgstr ""
+msgstr "，然而 data.table::melt 当前只支持输入 data.table 对象。请确保输入的是一个 "
+" data.table 对象，可以用 setDT("
 
 msgid ""
 "). If you intend to use a method from reshape2, try installing that package "
 "first, but do note that reshape2 is deprecated and you should be migrating "
 "your code away from using it."
 msgstr ""
+")。如果确实要使用 reshape2 中的方法，首先要安装这个包。需要注意，reshape2 已经"
+"弃用，你应该将代码迁移并且不再使用它。"
 
 msgid ""
 "and will attempt to redirect to the relevant reshape2 method; please note "
@@ -1202,69 +1205,80 @@ msgid ""
 "To continue using melt methods from reshape2 while both libraries are "
 "attached, e.g. melt.list, you can prepend the namespace like reshape2::melt("
 msgstr ""
+"即将转向到 reshape2 中的相关方法；请注意 reshape2 已经弃用，这个转向也已经弃用。"
+"如果要在 data.table 和 reshape2 同时附着的情况下继续使用 reshape2 中的 melt 方法，"
+"（例如 melt.list），你可以把命名空间写在函数名称前面，例如 reshape2::melt("
 
 msgid "Input patterns must be of type character."
-msgstr ""
+msgstr "输入的 patterns 必须是字符类型。"
 
 msgid "'data' must be a data.table"
-msgstr ""
+msgstr "'data' 必须是一个 data.table"
 
 msgid "'value.name' provided in both 'measure.vars'"
-msgstr ""
+msgstr "'value.name' 同时出现在了 'measure.vars'"
 
 msgid "and 'value.name argument'; value provided in"
-msgstr ""
+msgstr "和 'value.name' 参数中；'measure.vars' 中的值"
 
 msgid "'measure.vars' is given precedence."
-msgstr ""
+msgstr "将被优先使用。"
 
 msgid "Please provide a name to each element of 'measure.vars'."
-msgstr ""
+msgstr "请为 'measure.vars' 中的每个元素提供一个名称。"
 
 msgid ""
 "y and x must both be data.tables. Use `setDT()` to convert list/data.frames "
 "to data.tables by reference or as.data.table() to convert to data.tables by "
 "copying."
 msgstr ""
+"y 和 x 必须都是 data.table 对象。用 `setDT()` 可以把列表/数据框引用转换为 "
+" data.table，或者用 as.data.table() 进行复制转换。"
 
 msgid "maxgap must be a non-negative integer value of length 1"
-msgstr ""
+msgstr "maxgap 必须是一个长度为1的非负整数"
 
 msgid "minoverlap must be a positive integer value of length 1"
-msgstr ""
+msgstr "minoverlap 必须是一个长度为1的正整数"
 
 msgid "which must be a logical vector of length 1. Either TRUE/FALSE"
-msgstr ""
+msgstr "which 必须是一个长度为1的逻辑向量（TRUE/FALSE）"
 
 msgid "nomatch must either be NA or NULL"
-msgstr ""
+msgstr "nomatch 必须是 NA 或 NULL"
 
 msgid "maxgap and minoverlap arguments are not yet implemented."
-msgstr ""
+msgstr "maxgap 和 minoverlap 参数还未实现。"
 
 msgid ""
 "'y' must be keyed (i.e., sorted, and, marked as sorted). Call setkey(y, ...) "
 "first, see ?setkey. Also check the examples in ?foverlaps."
 msgstr ""
+"'y' 必须有主键（已经排序并且标记为已排序）。请先用 setkey(y, ...) 设置主键，"
+"可以参考 ?setkey 以及 ?foverlaps 中提供的例子。"
 
 msgid ""
 "'by.x' and 'by.y' should contain at least two column names (or numbers) each "
 "- corresponding to 'start' and 'end' points of intervals. Please see ?"
 "foverlaps and examples for more info."
 msgstr ""
+"'by.x' 和 'by.y' 每个应当包含至少两个列名（或序号），"
+"分别对应区间的起始点 'start' 和 结束点 'end'。请参考 ?foverlaps 以及提供的例子。"
 
 msgid ""
 "Invalid numeric value for 'by.x'; it should be a vector with values 1 <= by."
 "x <= length(x)"
 msgstr ""
+"无效的 'by.x' 数值，应该是一个向量，其中的值满足 1 <= by.x <= length(x)"
 
 msgid ""
 "Invalid numeric value for 'by.y'; it should be a vector with values 1 <= by."
 "y <= length(y)"
 msgstr ""
+"无效的 'by.y' 数值，应当满足 1 <= by.y <= length(y)"
 
 msgid "A non-empty vector of column names or numbers is required for by.x"
-msgstr ""
+msgstr "'by.x' 必须是一个非空向量，包含列名或者序号"
 
 msgid "A non-empty vector of column names or numbers is required for by.y"
 msgstr ""
diff --git a/po/zh_CN.po b/po/zh_CN.po
index 2b19c20e20..075400a6db 100644
--- a/po/zh_CN.po
+++ b/po/zh_CN.po
@@ -2341,39 +2341,39 @@ msgstr ""
 #: fread.c:1825
 #, c-format
 msgid "Internal error: sampleLines(%<PRIu64>) > allocnrow(%<PRIu64>)"
-msgstr ""
+msgstr "内部错误：sampleLines(%<PRIu64>) > allocnrow(%<PRIu64>)"
 
 #: fread.c:1829
 #, c-format
 msgid "  Alloc limited to lower nrows=%<PRIu64> passed in.\n"
-msgstr ""
+msgstr "  分配被限制在输入的更小的 nrows=%<PRIu64> 值上。\n"
 
 #: fread.c:1841
 msgid "[08] Assign column names\n"
-msgstr ""
+msgstr "[08] 指定列名\n"
 
 #: fread.c:1849
 #, c-format
 msgid "Unable to allocate %d*%d bytes for column name pointers: %s"
-msgstr ""
+msgstr "无法分配 %d*%d 字节给列名指针: %s"
 
 #: fread.c:1871
 #, c-format
 msgid "Internal error: reading colnames ending on '%c'"
-msgstr ""
+msgstr "内部错误：读取列名终止于 '%c'"
 
 #: fread.c:1889
 msgid "[09] Apply user overrides on column types\n"
-msgstr ""
+msgstr "[09] 使用用户指定的列类型\n"
 
 #: fread.c:1893
 msgid "  Cancelled by user: userOverride() returned false."
-msgstr ""
+msgstr "  用户已取消：userOverride() 返回 false。"
 
 #: fread.c:1903
 #, c-format
 msgid "Failed to allocate %d bytes for size array: %s"
-msgstr ""
+msgstr "无法分配 %d 字节给 size 数组：%s"
 
 #: fread.c:1910
 #, c-format
@@ -2382,34 +2382,36 @@ msgid ""
 "ignored. Only overrides to a higher type are currently supported. If this "
 "was intended, please coerce to the lower type afterwards."
 msgstr ""
+"试图覆盖第 %d 列 <<%.*s>>，将内部类型 '%s' 降级为 '%s' 的操作被忽略。只支持将列类型"
+"升为更高阶的类型。如果确定此操作，请完成之后再转换类型。"
 
 #: fread.c:1924
 #, c-format
 msgid "  After %d type and %d drop user overrides : %s\n"
-msgstr ""
+msgstr "  经过 %d 类型和 %d 丢弃用户覆盖：%s\n"
 
 #: fread.c:1932
 msgid "[10] Allocate memory for the datatable\n"
-msgstr ""
+msgstr "[10] 分配内存给 datatable\n"
 
 #: fread.c:1933
 #, c-format
 msgid "  Allocating %d column slots (%d - %d dropped) with %<PRIu64> rows\n"
-msgstr ""
+msgstr "  正在分配 %d 列位置（%d - %d 已丢弃），%<PRIu64> 行\n"
 
 #: fread.c:1987
 #, c-format
 msgid "Buffer size %<PRId64> is too large\n"
-msgstr ""
+msgstr "缓冲长度 %<PRId64> 过大"
 
 #: fread.c:1990
 msgid "[11] Read the data\n"
-msgstr ""
+msgstr "[11] 读取数据\n"
 
 #: fread.c:1993
 #, c-format
 msgid "  jumps=[%d..%d), chunk_size=%<PRIu64>, total_size=%<PRIu64>\n"
-msgstr ""
+msgstr "  jumps=[%d..%d)，chunk_size=%<PRIu64>，total_size=%<PRIu64>\n"
 
 #: fread.c:2005
 #, c-format
@@ -2421,7 +2423,7 @@ msgstr ""
 msgid ""
 "Column %d (\"%.*s\") bumped from '%s' to '%s' due to <<%.*s>> on row "
 "%<PRIu64>\n"
-msgstr ""
+msgstr "第 %d 列(\"%.*s\") 发生了从 '%s' 到 '%s' 的类型转换，由于 <<%.*s>> 出现在第 %<PRIu64> 行\n"
 
 #: fread.c:2262
 #, c-format
@@ -2433,19 +2435,19 @@ msgstr ""
 #: fread.c:2335
 #, c-format
 msgid ""
-"  Too few rows allocated. Allocating additional %<PRIu64> rows (now nrows="
-"%<PRIu64>) and continue reading from jump %d\n"
-msgstr ""
+"  Too few rows allocated. Allocating additional %<PRIu64> rows (now nrows=%<PRIu64>) "
+"and continue reading from jump %d\n"
+msgstr "  分配的行数太少。正在分配额外的 %<PRIu64> 行（当前 nrows=%<PRIu64>），并从跳跃 %d 继续读取\n"
 
 #: fread.c:2342
 #, c-format
 msgid "  Restarting team from jump %d. nSwept==%d quoteRule==%d\n"
-msgstr ""
+msgstr "  从跳跃 %d 重启组。nSwept==%d quoteRule==%d\n"
 
 #: fread.c:2362
 #, c-format
 msgid "  %d out-of-sample type bumps: %s\n"
-msgstr ""
+msgstr "  %d 样本外类型变更：%s\n"
 
 #: fread.c:2398
 #, c-format
@@ -2453,24 +2455,25 @@ msgid ""
 "Read %<PRIu64> rows x %d columns from %s file in %02d:%06.3f wall clock "
 "time\n"
 msgstr ""
+"读取 %llu 行 x %d 列，从 %s 文件（时钟时间 %02d:%06.3f）\n"
 
 #: fread.c:2405
 msgid "[12] Finalizing the datatable\n"
-msgstr ""
+msgstr "[12] 最后定型 datatable"
 
 #: fread.c:2406
 msgid "  Type counts:\n"
-msgstr ""
+msgstr " 类型数量：\n"
 
 #: fread.c:2408
 #, c-format
 msgid "%10d : %-9s '%c'\n"
-msgstr ""
+msgstr "%10d : %-9s '%c'\n"
 
 #: fread.c:2424
 #, c-format
 msgid "Discarded single-line footer: <<%s>>"
-msgstr ""
+msgstr "丢弃末尾行：<<%s>>"
 
 #: fread.c:2429
 #, c-format
@@ -2478,6 +2481,8 @@ msgid ""
 "Stopped early on line %<PRIu64>. Expected %d fields but found %d. Consider "
 "fill=TRUE and comment.char=. First discarded non-empty line: <<%s>>"
 msgstr ""
+"在第 %llu 行提前终止。预期有 %d 个字段但只找到 %d 个。可以考虑设置 "
+"fill=TRUE 和 comment.char=。 首个丢弃的非空行：<<%s>>"
 
 #: fread.c:2435
 #, c-format
@@ -2486,30 +2491,33 @@ msgid ""
 "%<PRIu64>: <<%s>>. If the fields are not quoted (e.g. field separator does "
 "not appear within any field), try quote=\"\" to avoid this warning."
 msgstr ""
+"发现并修复了样本外的错误引号。首次在第 %llu 行修复：<<%s>>。"
+"如果这些字段不在引号内（例如：字段间隔符没有在任何一个字段中出现），"
+"尝试用 quote=\"\" 来避免该警告。"
 
 #: fread.c:2439
 msgid "=============================\n"
-msgstr ""
+msgstr "=============================\n"
 
 #: fread.c:2441
 #, c-format
 msgid "%8.3fs (%3.0f%%) Memory map %.3fGB file\n"
-msgstr ""
+msgstr "%8.3fs (%3.0f%%) 内存映射 %.3fGB 文件\n"
 
 #: fread.c:2442
 #, c-format
 msgid "%8.3fs (%3.0f%%) sep="
-msgstr ""
+msgstr "%8.3fs (%3.0f%%) sep="
 
 #: fread.c:2444
 #, c-format
 msgid " ncol=%d and header detection\n"
-msgstr ""
+msgstr " ncol=%d 和表头检测\n"
 
 #: fread.c:2445
 #, c-format
 msgid "%8.3fs (%3.0f%%) Column type detection using %<PRIu64> sample rows\n"
-msgstr ""
+msgstr "%8.3fs (%3.0f%%) 列类型检测基于 %<PRIu64> 个样本行\n"
 
 #: fread.c:2447
 #, c-format
@@ -2517,6 +2525,8 @@ msgid ""
 "%8.3fs (%3.0f%%) Allocation of %<PRIu64> rows x %d cols (%.3fGB) of which "
 "%<PRIu64> (%3.0f%%) rows used\n"
 msgstr ""
+"%8.3fs (%3.0f%%) %llu 行 x %d 列 (%.3fGB) 的分配中已使用 %llu "
+"(%3.0f%%) 行\n"
 
 #: fread.c:2451
 #, c-format
@@ -2524,67 +2534,77 @@ msgid ""
 "%8.3fs (%3.0f%%) Reading %d chunks (%d swept) of %.3fMB (each chunk %d rows) "
 "using %d threads\n"
 msgstr ""
+"%8.3fs (%3.0f%%) 正在读取 %d 个块 (%d 已扫描) of %.3fMB (每个块 %d 行) "
+"使用 %d 个线程\n"
 
 #: fread.c:2453
 #, c-format
 msgid ""
 "   + %8.3fs (%3.0f%%) Parse to row-major thread buffers (grown %d times)\n"
 msgstr ""
+"   + %8.3fs (%3.0f%%) 解析到行处理线程的缓冲区（已增长 %d 次）\n"
 
 #: fread.c:2454
 #, c-format
 msgid "   + %8.3fs (%3.0f%%) Transpose\n"
-msgstr ""
+msgstr "   + %8.3fs (%3.0f%%) 转置\n"
 
 #: fread.c:2455
 #, c-format
 msgid "   + %8.3fs (%3.0f%%) Waiting\n"
-msgstr ""
+msgstr "   + %8.3fs (%3.0f%%) 正在等待\n"
 
 #: fread.c:2456
 #, c-format
 msgid ""
 "%8.3fs (%3.0f%%) Rereading %d columns due to out-of-sample type exceptions\n"
 msgstr ""
+"%8.3fs (%3.0f%%) 正在重读 %d 列，由于样本外类型异常\n"
 
 #: fread.c:2458
 #, c-format
 msgid "%8.3fs        Total\n"
-msgstr ""
+msgstr "%8.3fs        总计\n"
 
 #: freadR.c:84
 msgid ""
 "Internal error: freadR input not a single character string: a filename or "
 "the data itself. Should have been caught at R level."
 msgstr ""
+"内部错误：freadR 输入的不是单个字符串：文件名或者数据文本。"
+"该错误本应在 R 中被捕获。"
 
 #: freadR.c:92
 msgid ""
 "Input contains a \\n or is \")\". Taking this to be text input (not a "
 "filename)\n"
 msgstr ""
+"输入中包含 \\n 或者是 \")\"。输入将被当做数据文本（而非"
+"文件名）\n"
 
 #: freadR.c:95
 msgid "Input contains no \\n. Taking this to be a filename to open\n"
-msgstr ""
+msgstr "输入中不包含 \\n。输入将被当做文件名打开。"
 
 #: freadR.c:101
 msgid ""
 "Internal error: freadR sep not a single character. R level catches this."
 msgstr ""
+"内部错误：freadR sep 不是单个字符。R 中应该捕获此错误。"
 
 #: freadR.c:105
 msgid ""
 "Internal error: freadR dec not a single character. R level catches this."
 msgstr ""
+"内部错误：freadR dec 不是单个字符。R 中应该捕获此错误。"
 
 #: freadR.c:112
 msgid "quote= must be a single character, blank \"\", or FALSE"
-msgstr ""
+msgstr "quote= 必须是单个字符，空白 \"\"，或者 FALSE"
 
 #: freadR.c:137
 msgid "Internal error: skip not integer or string in freadR.c"
-msgstr ""
+msgstr "内部错误：freadR.c 中 skip 非整数或字符串"
 
 #: freadR.c:140
 #, c-format