148.join in 参加，加入

　　Students join in the school activities actively. 学生们积极参加学校活动。

　　He took off the coat and joined in the work. 他脱掉上衣加入到工作中去。

　　149.just now 眼下，目前，刚才，不久前 He left just now. 他刚离开。

　　He is learning painting from a well-known artist just now. 他现在正跟一个著名的画学家绘画。

　　150.keep an aye on 留意，照看

　　Keep an eye on the child while I am out. 我出去时麻烦照看一下这孩子。

　　Please keep an eye on my flowers in my absence. 我不在时帮我照看一下花。

　　151.keep one's word 遵守诺言

　　He always keeps his word. 他总是遵守诺言。

　　We must keep our word even if we should lose by it . 即使守信吃亏，我们也必须遵守。

　　152.keep pace with 与……齐头并进，与……并加齐驱

　　You must read the papers to keep pace with the times. 你必须阅读报纸来跟上时代。

　　His mental development kept up with the growth of his body. 他的智力发展与他的体格并头并进。

　　153.know about/of 听说，了解 I know of him, but I've never met him. 我听说过他，但从未见过他。

　　I didn't know about her father's death until last week. 直到上周我才得知她父亲去世的消息。

　　154.laugh at 因……而笑，嘲笑

　　We laughed at that funny-looking dog. 我们看到那长得有趣的狗都笑了。

　　They all laughed at the joke. 他们听了笑话后都笑了。

　　155.lead to 引起，导致

　　These words lead to misunderstanding. 这些话引起误解。

　　All roads lead to Rome. 条条大路通罗马。

　　156.learn from向……学习，从……学习

　　We learnt a lot from that teacher. 我们从那位老师那儿学到了许多。

　　We learn form life. 我们从生活中得到知识。

　　157.learn about/of 听说，获悉

　　I learnt of his death in the newspaper. 我从报上得知了的死讯。

　　His mother learned of her son's success from the newspaper. 他的母亲从报纸上得知她儿子成功的消息。

　　158.leave for 动身到

　　He left for Shanghai yesterday. 他昨天动身去了上海。

　　He left for seeking new experience. 他去寻求新的经历去了。

　　159.lie in 在于

　　The secret of good golf lies in the wrist action. 高尔夫的秘诀在于腕部的动作。

　　Success lies in diligence. 成功在于勤奋。

　　160.little by little 逐渐

　　Little by little, he learnt to write Chinese characters. 渐渐地，他学会了写汉字。

　　The infant crawled little by little. 这个婴儿一点点地向前爬。