English Grammar and Usage

'Just what the doctor ordered' is an idiomatic expression meaning something exactly what was needed or beneficial in a situation. The long holiday provided exactly what the man needed to feel refreshed, making this the perfect idiom for the context.

'À la prochaine' literally means 'until the next (time)' and is used as 'see you next time' or 'until next time'. Option C is correct. Options A (tomorrow) and D (bye) are too specific or incorrect.

Comment allez-vous uses the formal 'vous' form, meaning 'How are you?' in a polite or formal context. Comment vas-tu would be the informal 'tu' form. Option A is 'Ou allez-vous?' (Where are you going?), and Option D would be 'Quoi de neuf?' for What's new?

Je vous en prie is the standard formal response to 'thank you' in French, meaning 'you are most welcome' or 'don't mention it.' Option A would be 'Je vous remercie' (I thank you), Option B is 'A bientôt' (see you later), and Option D would be something like 'Je me dépêche' (I'm in a hurry).

'At last' is a common English idiom used to express that something has finally happened after a long wait or delay. It conveys a sense of relief or achievement.

The phrase 'completely worn' is an incomplete idiom in this context. It should be 'completely worn out' to correctly indicate extreme exhaustion. The other parts of the sentence are grammatically sound.

The sentence is grammatically correct. It uses proper subordinate clauses and correct idiomatic phrasing ('so huge an animal') to describe the reaction of people to a beached whale.

The conjunction 'that' is used to introduce a noun clause acting as the object of the verb 'hear'. It reports the information received. 'Whether' would imply doubt, which doesn't fit the declarative nature of the statement.

The verb 'found' (meaning to establish) forms its past tense as 'founded'. Example: 'They founded the company in 1990.' This is a regular verb formation.

'Improve' is only a verb. The noun form requires adding '-ment' to become 'improvement'. You cannot use 'improve' as a noun in standard English.

The past tense of 'find' is 'found'. This irregular verb follows patterns like bind-bound and grind-ground. Example: 'Yesterday, I found my lost wallet.'

'Tomorrow' is the correct spelling of the day following today. The word combines 'to' + 'morrow' with double 'r'. Common errors include adding extra letters or missing the 'r'.

'You' and 'them' are personal pronouns in this sentence. 'You' is the subject pronoun addressing someone being spoken to, while 'them' is the object pronoun referring to certain people or things. 'Have' is a helping verb (auxiliary) and 'seen' is the main verb. The sentence has no actual nouns, only pronouns replacing them.

The question 'How long' asks about duration or time span, so the answer must specify a period of time. 'For three hours' (option D) correctly indicates duration using the preposition 'for'. Options A, B, and C answer different questions - 'With whom' (Bob), 'Where' (in my room), and 'What subject' (English) respectively.