When you are in Singapore, you can go about (1) .................... taxi , by bus, or by underground. I myself prefer the underground (2) ................... it is fast, easy and cheap. The underground is therefore usually quicker (3) ............. taxis or buses. If you do not know Singapore very well, it is difficult (4) ............ the bus you want. On the underground, you find good maps that tell you the names of the stations and show you how to get to them, so that it is easy to find your way. 1. A. at B. in C. by D. on 2. A. but B. because C. when D. and 3. A. so B. like C. than D. to 4. A. to find B. find C. finding D. found  Tick nhanh nèee