Four-strokes
(four-stroke 的復(fù)數(shù)) adj. 四沖程的（內(nèi)燃機）; 四行程
?? 詞語組成解析
four
[f?r]
num. 四;四個;第四;
n. 四的;四個一組之物;
n. 中風(fēng)
??? 情景例句
My mother doesn't mind who comes to stay, she's very easy-going.
我母親不在乎有什么人來往，她十分隨和。
What would you say if I told you I couldn't go with you?
如果我告訴了你我不能和你一起去你將說什么？
Letter
3第三封信