Mother tongue, honeymoon and a small amount of gold
Saeed Ghasemzadeh from Iran from Marga from Spain writes:
  Saeed asks: Why do we say mother tongue and not mother language and why honeymoon and not honey month?
Marga asks: Do you say: a small amount of gold or a little amount of gold? What is the difference?
Roger Woodham replies:
Honeymoon is a compound noun, meaning a holiday spent together by a couple immediately after their marriage.
We also have the expression honeymoon period, meaning the beginning of a period of time when everything is pleasant in a relationship and partners don't criticise each other:
They plan to go on honeymoon to Thailand for a month.
The honeymoon period for this new government is now over.
Honey month is an impossible combination and would not make any sense now, even though the word honeymoon was originally used to describe the first month of marriage. The reference to the moon (and therefore lunar month) is ironic: everybody knows that as soon as the moon is full, it starts to wane and dies.
Mother tongue - native language
Mother tongue is another fixed collocation. You are right, Saeed, we do not say mother language. Instead, we would normally say native language, though native tongue is also possible, see below:
Her mother tongue was Russian, but you would never have guessed it from her perfect pronunciation of English.
You should acquire a perfect grasp of your native tongue before you start to learn a foreign language.
The greater part of learning a foreign language, Saeed, is all about knowing which words naturally occur together. The examples given so far are relatively straightforward but it becomes more complicated when we look at the words which small and little naturally occur with.
A small house / a little house
When little and small both mean not large, with some nouns they can be used interchangeably with little or no difference in meaning:
They lived in a little house in the country.
They lived in a small house in the country.
However, little also suggests that you feel sympathy for something, whereas small is more neutral and does not suggest this. Compare the following:
He's only a little boy. He doesn't know the difference between right and wrong. ~ He may be a small child, but that doesn't excuse his behaviour!
Because little invokes sympathy, it is often used with other adjectives like nice, sweet, tiny, pretty, poor. Small cannot be used in this way:
This job is a nice little earner. Maximum reward for minimum effort.
She's a sweet / pretty little thing. Always has a smile on her face.
They live in this tiny little bed-sit in Shepherds Bush.
Little = not much
Little is also more complicated than small because it can also mean not much. Small can only mean not large. Compare the following:
Will you have beer or wine with your meal? ~ I'd like a little wine, please. A small glass of red wine would be nice.
Would you like a large or a small coffee? ~ Oh, a small coffee please. I shan't sleep tonight if I have a large one.
Abstract nouns that often follow little (meaning not much) include hope, chance, change, effect, use and point:
There's little chance / hope of finding any survivors after such a massive explosion. I see little point in continuing the rescue mission.
There has been little change in his condition over the last seventy two hours. The new drugs appear to have had little effect.
Small amount / small number
When we define small as not large we are thinking about small in size, amount or number:
These shoes are too small. They really don't fit me at all.
I only had a small amount of gold but enough to purchase everything I needed.
A disappointingly small number of people entered the competition.
Note that small also combines readily with very and few as well as with too. Few cannot be combined with little and little is not normally used with very or too:
I noticed that there were a few small mistakes in your essay.
The phone box was very small, but we all managed to squeeze in.
A pierced tongue