如图为人体某处的血管及血液流动示意图，叙述正确的是（  ）

根据所给音标、汉语或首字母提示写出下列句中所缺单词。

Don't forget to____ /nɔk/ at the door before entering the meeting room. 

The new law is so strict that it doesn't____ / ə' lau/ any indoor smoking.

He got____ /drest/ quickly after taking a shower.

People throw l____  into the river and make it really dirty.

Nobody knew what to say and they just sat there in s____ .

The medicine should be taken t____  a day after meals.

When he grew up, he turned into an____ （诚实）and helpful person.

It's said that the terrible weather in this____ （季节）caused the ship accident.

A sweeping robot is____ （确切地）what I want for my house.

The fantastic world surely ____ （属于）to young people and the future.

若${\left(x^2-\frac{1}{x^3}\right)}^n$的展开式中存在常数项，则n可以为（　　）