diff --git a/library/io.po b/library/io.po
index eac22ef555..00c8045050 100644
--- a/library/io.po
+++ b/library/io.po
@@ -798,12 +798,16 @@ msgid ""
 "Return ``True`` if the stream supports writing.  If ``False``, :meth:`!"
 "write` and :meth:`truncate` will raise :exc:`OSError`."
 msgstr ""
+"如果串流支援寫入，則回傳 ``True``。如果是 ``False``，:meth:`!write` 和 :meth:"
+"`truncate` 將會引發 :exc:`OSError`。"
 
 #: ../../library/io.rst:456
 msgid ""
 "Write a list of lines to the stream.  Line separators are not added, so it "
 "is usual for each of the lines provided to have a line separator at the end."
 msgstr ""
+"將一個包含每一行的 list 寫入串流。這不會新增行分隔符號，因此通常提供的每一行"
+"末尾都有一個行分隔符號。"
 
 #: ../../library/io.rst:462
 msgid ""
@@ -811,10 +815,12 @@ msgid ""
 "implementation of this method that calls the instance's :meth:`~IOBase."
 "close` method."
 msgstr ""
+"為物件銷毀做準備。:class:`IOBase` 提供了這個方法的預設實作，該實作會呼叫實例"
+"的 :meth:`~IOBase.close` 方法。"
 
 #: ../../library/io.rst:469
 msgid "Base class for raw binary streams.  It inherits :class:`IOBase`."
-msgstr ""
+msgstr "原始二進位串流的基底類別。它繼承自 :class:`IOBase`。"
 
 #: ../../library/io.rst:471
 msgid ""
@@ -823,12 +829,15 @@ msgid ""
 "(this functionality is done at a higher-level in buffered binary streams and "
 "text streams, described later in this page)."
 msgstr ""
+"原始二進位串流通常提供對底層作業系統設備或 API 的低階存取，並不嘗試將其封裝在"
+"高階基元 (primitive) 中（這項功能在緩衝二進位串流和文字串流中的更高階層級完"
+"成，後面的頁面會有描述）。"
 
 #: ../../library/io.rst:476
 msgid ""
 ":class:`RawIOBase` provides these methods in addition to those from :class:"
 "`IOBase`:"
-msgstr ""
+msgstr ":class:`RawIOBase` 除了 :class:`IOBase` 的方法外，還提供以下這些方法："
 
 #: ../../library/io.rst:481
 msgid ""
@@ -837,6 +846,9 @@ msgid ""
 "only one system call is ever made.  Fewer than *size* bytes may be returned "
 "if the operating system call returns fewer than *size* bytes."
 msgstr ""
+"從物件中讀取最多 *size* 個位元組並回傳。方便起見，如果 *size* 未指定或為 -1，"
+"則回傳直到檔案結尾 (EOF) 的所有位元組。否則，只會進行一次系統呼叫。如果作業系"
+"統呼叫回傳的位元組少於 *size*，則可能回傳少於 *size* 的位元組。"
 
 #: ../../library/io.rst:486
 msgid ""
@@ -844,17 +856,19 @@ msgid ""
 "If the object is in non-blocking mode and no bytes are available, ``None`` "
 "is returned."
 msgstr ""
+"如果回傳了 0 位元組，且 *size* 不是 0，這表示檔案結尾 (end of file)。如果物件"
+"處於非阻塞模式且沒有可用的位元組，則回傳 ``None``。"
 
 #: ../../library/io.rst:490
 msgid ""
 "The default implementation defers to :meth:`readall` and :meth:`readinto`."
-msgstr ""
+msgstr "預設的實作會遵守 :meth:`readall` 和 :meth:`readinto` 的實作。"
 
 #: ../../library/io.rst:495
 msgid ""
 "Read and return all the bytes from the stream until EOF, using multiple "
 "calls to the stream if necessary."
-msgstr ""
+msgstr "讀取並回傳串流中直到檔案結尾的所有位元組，必要時使用多次對串流的呼叫。"
 
 #: ../../library/io.rst:500
 msgid ""
@@ -863,6 +877,9 @@ msgid ""
 "`bytearray`. If the object is in non-blocking mode and no bytes are "
 "available, ``None`` is returned."
 msgstr ""
+"將位元組讀入一個預先分配的、可寫的 :term:`bytes-like object` （類位元組物"
+"件） *b* 中，並回傳讀取的位元組數量。例如，*b* 可能是一個 :class:"
+"`bytearray`。如果物件處於非阻塞模式且沒有可用的位元組，則回傳 ``None``。"
 
 #: ../../library/io.rst:508
 msgid ""
@@ -874,12 +891,17 @@ msgid ""
 "to it.  The caller may release or mutate *b* after this method returns, so "
 "the implementation should only access *b* during the method call."
 msgstr ""
+"將給定的 :term:`bytes-like object` （類位元組物件），*b*，寫入底層的原始串"
+"流，並回傳寫入的位元組大小。根據底層原始串流的具體情況，這可能少於 *b* 的位元"
+"組長度，尤其是當它處於非阻塞模式時。如果原始串流設置為非阻塞且無法立即寫入任"
+"何單一位元組，則回傳 ``None``。呼叫者在此方法回傳後可以釋放或變更 *b*，因此實"
+"作應該只在方法呼叫期間存取 *b*。"
 
 #: ../../library/io.rst:521
 msgid ""
 "Base class for binary streams that support some kind of buffering. It "
 "inherits :class:`IOBase`."
-msgstr ""
+msgstr "支援某種緩衝的二進位串流的基底類別。它繼承自 :class:`IOBase`。"
 
 #: ../../library/io.rst:524
 msgid ""
@@ -888,6 +910,9 @@ msgid ""
 "input as requested or to consume all given output, at the expense of making "
 "perhaps more than one system call."
 msgstr ""
+"與 :class:`RawIOBase` 的主要差異在於，:meth:`read`、:meth:`readinto` 及 :"
+"meth:`write` 方法將分別嘗試讀取所請求的盡可能多的輸入，或消耗所有給定的輸出，"
+"即使可能需要進行多於一次的系統呼叫。"
 
 #: ../../library/io.rst:529
 msgid ""