Câu hỏi: ................  I can’t go to the conference as I’ve got to do to Sydney on business.

A. Frankly 

B. Unfortunately 

C. Personally

Câu 1: These drugs are the best medicine available as a treatment at the moment, ............ they are expensive, unfortunately.

A. although

B. because

C. so

Câu 2: What ........... in order to get a permitto work in your country?

A. do I need to do

B. must I do

C. ought I do 

Câu 3: Many children these days do not have ahealthy diet................ is possible thatthis is because less healthy foods are cheaper than healthy ones. 

A. What

B. That

C. It

Câu 4: Do you have any knowledge …………….how our education system works?

A. of

B. on

C. for

Câu 5: In the past we threw a lot of ourkitchen waste away, but today many items such as plastic bottles and newspapers .............. 

A. are recycled

B. recycle

C. need recycling

Câu 6: She got a terrible mark in the exam so she ........ very hard at all.

A. mustn’t have worked

B. can’t have worked

C. didn’t work