单选:is ___ easy to learn to swim?a.that b.it c.this

单选:is ___ easy to learn to swim?a.that b.it c.this
单选:is ___ easy to learn to swim?
a.that b.it c.this

单选:is ___ easy to learn to swim?a.that b.it c.this
B
变为陈述句是It is easy to learn to swim.
这里it做形式主语,真正的主语是to learn to swim
所以,这句话也可以说是To learn to swim is easy.