Silence

11 you put another 1 next to 1 becomes 11

Short (you just add 'er')

There are no stairs in a one-story house

A candle

It can have a hole in it

5 men, 10 children and 20 women
If x = the number of men, then x + 2x + 4x =35
therefore 7x = 35
so x = 5

808
Multiply the first two numbers in the preceding line;
multiply the next two numbers in the preceding line;
multiply the last two numbers in the preceding line

5
The numbers are the alphabetical positions of the letters, spelling FACADE:
6-F; 1-A; 3-C; 1-A; 4-D; 5-E.

Lemonade
None of the rest are drinks.

The pregnant lady’s baby

They all fall in the middle
15 February was the middle of February (1984 being a leap year);
2 July was the middle day of the year 1983;
and 16 December was the middle of December.