Fill in the Blanks

The sentence has two past actions: 'had completed' (past perfect) and the blank. Past perfect is used for the earlier action, and simple past is used for the later action. Since completing the work happened before the father came, 'had completed' is already correct for the first action. The father's action came after, so it uses simple past 'came'.

 The antecedent in time of simple past 'he arrived' is past perfect 'had wriiten'.

 This is the case of simple present tense.

The phrase 'as though' introduces a hypothetical or contrary-to-fact situation, which requires the subjunctive mood. For statements that are clearly contrary to reality (like someone being angry when they're not), we use 'were' instead of 'was'. This is the subjunctive form of 'to be' used in hypothetical situations after 'as though' or 'as if'.

 "Just now" denotes present tense , so 1 is correct

 This is the case of past tense.

 This is the case of past tense

 Since this is the case of past tense , Hence 3 is correct

This is a first conditional sentence describing a real possibility in the present/future. The structure is: If + present simple, ... will + base verb. 'If he is honest' uses present simple, so the result clause uses 'will prosper' (will + base verb). First conditionals express likely or possible future results based on present conditions.

 "Last night" denotes past tesne. Hence, "had" is correct

Case of past tense, hence 1 is correct

This is a first conditional sentence expressing a real possibility. When the if-clause uses present tense (or any form implying a real condition), the result clause uses 'will'. Here, 'You will succeed' is the result, so the if-clause should use present simple 'work' (not 'worked' or 'had worked'). First conditionals follow the pattern: If + present simple, ... will + base verb.

 This is the case of past tense , hence 2 is correct.

 Since this is an "interrogative" sentence, Hence we will use first form of the verb

 "Last 10 years" denote past tense. Since, this is the case of past perfect continous tense , hence 3 is correct.