Professor Johnson is said _____ some significant advance in his research in the past years.

_____ at in this way, the present economic situation doesn't seem so gloomy.

If only I _____ play the guitar as well as you!

____The water left in the kettle, the doctor put several things he unwrapped from a handkerchief.

只有在我过度劳累的时候，在我长时间不间断地工作的时候，在我感到内心空虚，需要充实的时候，我才会感到寂寞。有时，外出演讲回来，见了许多人，讲了许多话，心中满是纷乱的体验需要整理，偶尔也会觉得孤独。于是有那么一会儿，我会感到整个房子非常大，空荡荡的。不知此时的自我又藏匿于何处。这时，我会给花草浇浇水，挨个瞅瞅，仿佛它们是活生生的人一样，或是喂喂两只小猫，亲手做顿饭菜，这样自我就慢慢地重新找回。