May I _____ your bike—Sure. But please give it back to me thisafternoon.

下面各句中加点的成语，使用正确的一项是（ ）

The population of the world in 20th century became very much _________than that in 19th.

Little Bob is often educated by his parents to be good and friendly to anybody even if ________[ ]

I study really hard ________ I can make my dream come true.