31. —You should make it a rule to do more exercise in your spare time. — I think your suggestion really deserves__________.
I hear____ boys in your school like playing football in their spare time, though others prefer basketball.
Of the two sisters, Betty is_______ one, and she is also the one who loves to be quiet.
Letterboxes are much more _______ in the UK than in the US, where most people have a mailbox instead.
I wish you’d do ________ talking and some more work. Thus things will become better.
Green products are becoming more and more popular because they are environmentally _____.