The young scientist has made such great achievements in his chosen field ______ nobody else can make.

下列各句中，表达得体的一句是（ ）

What depressed her was that although she kept waving her hand, nobody seemed _______ her new watch.

It is the first time that Martin has been to the South Pole, ________?

ion, people won’t have the motivation or the joy necessary for creative thinking.