It is a colloquial term that is generally used by people who are poorly educated. It is sometimes used when one cannot remember a person's name, but it is considered rude. It is much better to say 'a person, whose name I cannot remember...'

He was so upset that he 'quit' programme. In other words, he left the programme, stopped working for the programme, had no contact with it any more.

It should be 'Make yourself comfortable' as the above answers state. Have you been receiving my emails? I am concerned that my email server might not be working properly, and I want to make sure they are reaching you.

The mother sighed when she heard that her baby was out of danger. The father banged on the door to wake the sleeping children. The doves enjoyed eating the grains that were scattered on the floor. The cook showed his recipes in a cocksure manner. The college students are loquacious. The ending sound of the word 'bang' is 'ng'. You will need the middle of your tongue to be touching the middle of your upper palate when you pronounce this soft sound. Cocksure is pronounced 'cock-shor'. Locquacious is pronounced 'loc-way-shious'

They essentially both mean a large gathering. However, the term 'horde' is usually used to describe a gathering of bad people, while the word 'throng' could be used for a gathering of either good or bad people.

Pile and mound both mean a gathering of inanimate objects, such as a pile of sticks, or a mound of dirt. The word 'drift' means to 'go away from', as in 'The boat drifted away (from me) in the water.'

'Absence makes the heart grow fonder' is a quote, a type of proverb. It means that when you are away from somebody, you will long to be with them.