l字母开头
lack[læk] v. 缺乏(be short of)n. 缺乏(absence, shortage)，短缺
lack of ... ...的缺少
for lack of... 因缺乏...
e.g. he is lack of passion热情 in work.
lag[læg] n./vi.(lagged, lagged, lagging) 落后(drop behind, get behind)
lag behind ... 落在...的后面
e.g. the children always lag behind when we go for a walk.
land [lænd] n. 陆地(earth)，土地(soil)， 国土v. (使)登陆，靠岸
land transportation 陆上运输
forest land 林地
e.g. we are glad to be on land again.
laugh [lɑ:f] vi./n. 笑
laugh at... 嘲笑...
laugh... off 用笑摆脱...
laugh in sb.'s face 当面嘲笑某人
laughter ['lɑ:ftə] n. 笑, 笑声
e.g. don't laugh at him. laughter is the best medicine.
launch[ lɑ:ntʃ] vt.发射(导弹、火箭等)(send off, set off)，发起(begin, initiate, set up, start ),使（船）下水 n. 发射，（船）下水
launch an artificial satellite ['sætəlait] 发射人造卫星
e.g.they have launched a man-made satellite successfully.
law [lɔ:] n. 法律，规律(rule, principle) ，定律
observe/keep/follow a law 守法
enforce a law 执法
the laws of nature 自然规律
e.g.i have to follow nature's law.
lay [lei]vt.(laid, laid, laying) 放置(put, place)，铺设，布置，产(卵)
lay... aside 搁置..., 积蓄...
lay down... 制定...，放下...
lay out 布置, 展示
lay... off (临时)解雇...
e.g. we shall have to dig挖under the river to lay the sewage 污水pipe.管道
lead [li:d] v.(led, led, leading) 领导(guide, direct, head, supervise)，为---带路，通向，导致 n. 铅， 领导 ，领先
lead sb. in doing... 领导某人做...
lead a ... life 过...生活
lead to... 导致..., 通向...
take the lead 带头
e.g. the guide向导led us to the river.
leader ['li:də] n. 领袖，领导者
e.g. he's a follower, not a leader.
leadership n. 领导能力
under the leadership of... 在...的领导之下
e.g. he shows quality才能 of leadership.
learn [lə:n]v. (learnt/learned, learnt/learned, learning)学习(study)，学会(acquire, grasp, master)，得知(know)， 记住(bear in mind, memorize)
learn ...by heart 记住...
learn from... 向...学习
learn of/about... 得知...， 了解...
e.g.one is never too old to learn. 活到老，学到老。