Bill bought _____useful book．_____book is very interesting．（　　）

A．a；TheB．a；AC．an； TheD．an； A

My brother has lost his watch． Now he is looking for_____．（　　）

A．oneB．thisC．thatD．it

In February， Chinese tech company Huawei _____Mate X， a foldable（可折叠的）5G mobile phone．（　　）

A．is introducingB．introduced

C．introducesD．was introduced

Do you know Hong Kong﹣Zhuhai﹣ Macao Bridge（港珠澳大桥）？

Yes． it is_____cross﹣sea bridge in the world．（　　）

A．the longerB．longest

C．the longestD．longer

The beautiful lady with glasses over there looks like our English teacher．

It _____be her． She has gone abroad．（　　）

A．can'tB．may notC．mustn'tD．needn't