Putting out forest fire is regarded as one of _____ problems in the world.( )
difficult
more difficult
most difficult
the most difficult
Swimming is, of course, interesting.But ________ we plan to go swimming, being safe must come first. ( )
though
when
unless
In summer vacation, I want to help parents ________ clothes in the square to make some money.
Good idea. It's also a good chance to know about the society.( )
lend
give
sell
As you listen, you can write down the key information such as names and numbers. The ________ will help you understand and remember what you hear. ( )
notes
photos
letters
Tu Youyou and Yuan Longping set good examples to young people. Everyone should be proud of ________. ( )
us
you
them
You ______ lunch at school.So you don't have to bring your own food.( )
will give
are given
have given