leave sb by oneself 独自留下某人

needn't=don't have to 不需

it's+形容词+to do sth

make sb to do sth 让某人做某事

let sb to do sth 让某人做某事

enjoy oneself=have a good time 玩得开心

tell sb (not)to do sth 告诉某人做某事

ask sb (not)to do sth 询问某人做某事

be(not)+形容词+enouth+to do sth

be+too+形容词+to do sth

take care of=look after 照顾

each+of 固定搭配

as soon as 一……就

see sb doing sth 看见某人正在做某事

see sb do sth 看见过某人做某事

make it+形容词+to do sth

enjoy/help/teach+oneself 靠自己

reach=get to=arrive in/at 注：arrive in表示到达较大的地方，比如一个国家，一座城市等;arrive at表示到达较小的地方，如学校，电影院等。

have been to 曾经去过某地(现在已经回来了)

have been in 一直在某地(现在仍在某地)

have gone to 去了某地(现在正在去的途中，还没回来)

现在完成时：have(has)+动词过去分词

look forword to+动词ing

diveded into 把……分成

a little=a bit of 一点点

too……to+动词原形

n+一段时间 表示将来

将来时表达形式：be going to do sth=will do sth=be doing sth