英文謎語功課!!1小時內!!20點!!急!!

In rainy days and stormy days, a dog most likely to enter a house because dogs do not like wet place or wet weather.
The middle of Paris is letter 'r'.
MTR(Mass Transit Railway) can go backward or forward because when it reaches the final station like Yau Ma Tei,Tsuen Wan etc. the train head becomes its tail and the train tail becomes its train head.

2008-03-06 14:40:45 補充：
In rainy days and stormy days, a dog most likely to enter a house because dogs do not like wet place or wet weather. They want to find shelters in rainy days or stormy days.

1. i don't know
2. R
3. racecar

2008-03-07 05:06:36 補充：
#3: when the question says 'it's spelt the same backwards and forwards', it is asking for words like 'peep' - it's the same word whether you write it from the front or from the back. the question is not referring to what the vehicle does.

2008-03-07 05:08:59 補充：
#2: it's a question that is meant to be a joke - lots of such things in English. i would expect the answer to be R, or air might also be right.

2008-03-07 05:12:41 補充：
#1: there is an idiom that says 'it's raining cats and dogs', but i don't see any relevance here. the questions here tells me that the whole thing is a word game - so i don't suppose any answer that comes from common knowledge works...

1)when its master come back home
2)Falling tower

2. r
pa r is

i dont know the others, sorry