English Grammar and Usage

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.

 The past participle of lay is lain. Hence, option 4 is correct.

 Had to is correct as it is the past participle of must.

The verb 'shear' has two acceptable past participle forms: 'sheared' (regular formation) and 'shorn' (irregular formation). Both are grammatically correct and used in different contexts - 'sheared' is more common when referring to cutting wool, while 'shorn' is typically used in poetic or literary contexts.

The past participle of 'slay' is 'slain' (the verb forms are: slay-slew-slain). This is an irregular verb that follows the pattern of i-a-u vowel gradation. 'Slayed' is incorrect, and 'slay' is the base form, not the past participle.

The past participle of 'hew' is 'hewn' (verb forms: hew-hewed-hewn). Option B 'hewed' is the simple past tense, not the past participle. The past participle is formed with the -en suffix typical of some irregular verbs like 'sow-sown' or 'mow-mown'.

The verb 'come' is irregular in that its past participle is identical to its base form: 'come' (verb forms: come-came-come). The past form 'came' is not used as the past participle. This is similar to other verbs like 'become-became-become' and 'run-ran-run'.