English Grammar and Usage

The simple future tense 'will be' is correct for predicting a certain future event. The conditional 'would be' is used for hypothetical situations, 'shall be' is formal first-person future, and 'be' is grammatically incorrect without an auxiliary verb.

The past perfect tense 'had gone' is correct because the action (children going for a picnic) happened before the past reporting verb 'said'. Past perfect (had + past participle) shows the earlier of two past events. 'Has gone' and 'have gone' are present perfect tenses.

The future continuous tense 'will be living' is correct because 'at this time of next month' indicates an action that will be in progress at a specific future time. Future continuous (will be + verb-ing) describes ongoing future actions. 'Live' is simple present, and 'will living' is grammatically incorrect.

The past perfect tense 'had won' is correct because the winning happened before the past reporting verb 'said'. Past perfect shows the earlier of two past actions. 'Won' is simple past, 'have won' is present perfect, and 'win' is present tense.

The simple future tense 'will stay' is correct for expressing a planned future action or intention. 'Will be stay' is grammatically incorrect, 'would stay' is conditional (not appropriate here), and 'shall stay' is more formal and typically first-person.

The future perfect tense 'will have finished' is correct because it describes an action that will be completed before a specific future time ('by the time you come back'). Future perfect (will have + past participle) shows actions completed before future reference points. 'Has finished' is present perfect and 'finished' is simple past.

The future perfect tense 'will have discussed' is correct because 'by next Sunday' indicates the action will be completed before a specific future time. Future perfect (will have + past participle) is used for actions finished by future deadlines. 'Discuss' is simple present, 'will discuss' is simple future, and 'will be discussing' is future continuous.

Since 'will' has been used, the verb succeeding it will in simple present tense. Hence, 'take' is the correct answer.

'Usually' is an adverb of frequency and is followed by a verb in the present tense form. Hence, 'plays' is the correct answer.

The phrase 'since morning' indicates an action that began in the past and continues to the present. Present perfect continuous 'has been digging' correctly shows this ongoing duration. Simple past or present tenses don't capture the continuation aspect.

'He' is a third person singular. Hence, 'has' is used with the third person singular.

The time marker 'three years ago' indicates a completed past action, requiring simple past tense. 'Bought' is the past tense of 'buy'. Option A is present tense, B is past continuous, and D uses 'brought' (past of 'bring') instead of 'bought'.

'Will have finished' fits best in the given sentence.

'Last Monday' is a specific past time reference, requiring simple past tense. 'Stayed' correctly describes the completed action. Present tense 'stay' and present continuous 'is staying' don't match the past timeframe.

When two actions happen in the past in succession, the first action takes up past perfect form of the verb while the second takes up simple past form of the verb.