Disappeared (from the verb disappear) is not used like an adjective: (i) Get lost, as without warning or explanation: ‘His wife has disappeared with the children.’(ii) Become invisible or unnoticeable: ‘The effect disappeared when the day broke.’ (iii) Cease to exist: ‘One day our problems will disappear.’ (iv) Become less intense and fade away gradually: ‘The pain in my back just disappeared.’

Have difficulty/difficulties (in) doing sth (NOT a difficulty): ‘Sometimes he has difficulty in making himself understood.’

Have difficulty/difficulties (in) doing sth (NOT to do): ‘You should have no difficulty in passing the exam.’

In (great/more/some) detail (WITHOUT – s): ‘The victim described about the attacker in detail.’ ‘Having actually stayed at the hotel, he was able to describe it in great detail.’

An isolated fact that is considered separately from the whole: ‘Several of the details are similar.’

Despite, and in spite of (Regardless of) are prepositions (NOT conjunctions). Despite sth (WITHOUT of): ‘Despite the heat, she wouldn’t take her coat off.’

In spite of sth (WITH of): ‘In spite of the heat, she wouldn’t take her coat off.’

(i) Do not confuse depend on/upon and the more formal phase, be dependent on/upon. Compare: Depends on/upon: ‘The speed of a car depends on the size of the engine.’ Be dependent on/upon: ‘The speed of a car is dependent on the size of the engine.’(ii) Depends on/upon means ‘be shaped or determined by’(it is not used in progressive tenses): ‘His success depends on/upon his effort.’  (iii) ‘It depends on whether (NOT if): ‘We don’t know yet. It all depends on whether the car is fixed in time.’

A show or display; the act of presenting something to sight or view; hold/stage a demonstration (NOT make): ‘In London, students and lecturers staged a mass demonstration against the proposed education cuts.’ ‘Many demonstrations have been held in protest against the level of pollution.’

(i) Request urgently and forcefully: ‘The victim’s family is demanding for compensation.’ (ii) Claim as right or due: ‘The bank demanded the payment of the loan.’(iii) Ask to be informed of: ‘I demand an explanation.’(iv)To call for or require as just, proper or necessary: ‘The situation demands a lot of personal sacrifice.’ (v) Lay legal claim to: ‘She demanded half of her husband’s property as alimony.’

A demand for sth (NOT of): ‘Ford has increased production to meet the demand for its new range of cars.’

An agreement between two or more parties: ‘They closed the deal after a week of negotiating.’

A great/good deal of (to a great degree or extent or quantity) + uncountable noun: ‘He derived a great deal of pleasure from the world tour.’

Deal in: Do business or buy or sell: ‘The company deals in textiles.’

Deal with: (i) Be about (of books, articles etc.): ‘The book deals with insects.’ (ii) Take action with respect to: ‘He knows how to deal with this problem.’ (iii) Be in charge of, act on, or dispose of: I can deal with this crew of workers.’ (iv) Behave in a certain way towards others: ‘She fairly deals with her colleagues.’