ysics teacher and English teacher always givetheir lessons in a lively and clear way,____ greatly benefits us students

______ the rice by washing it, then______ it in boiling water.

The world’s population is growing and there is land and water for growing rice.

We believe ________ we can find out the wonder drugs to H7N9 bird flu.

Linda thinks ______ conversations with friends in English is really helpful.