It's good for you to keep_____when something difficult needs___.A trying;to do B trying;doing

问题描述:

It's good for you to keep_____when something difficult needs___.A trying;to do B trying;doing
C to try;to do
D to try;to be done

选B.keep doing坚持做某事;
sth.needs doing 某物需要...,动名词doing是主动形式表示被动意思.
也可用:sth.needs to be done