Not only my parents but also I _______ regretting the change of school.

• are
• is
• am
• No option is appropriate
Correct Option: C  [ am ]

Remark: in case "Not only...but also" the verb should agree with the subject closest to the verb.

None of the students ___________ responded.

• have
• were
• is
• has
Correct Option: A  [ have ]

Remark:

Each of the students _______ given a task to complete.

• were
• was
• have
• have been
Correct Option: B  [ was ]

Remark: If a subject is modified by the words "each" or "every" that subject is singular and will take a singular verb.

Either you or I should ___________ the lead.

• took
• taking
• takes
• take
Correct Option: D  [ take ]

Remark:

Each of the students ________ responsible for keeping this room clean.

• are
• has
• is
• have
Correct Option: C  [ is ]

Remark:

Unless we ______ now we can't be on time.

• will start
• start
• starts
• will be starting
Correct Option: B  [ start ]

Remark:

Not only Pinki but also her friends _________ buying books.

• is
• has
• have
• are
Correct Option: D  [ are ]

Remark:

The team _______ playing well.

• have
• were
• is
• are
Correct Option: C  [ is ]

Remark: "team" is a collective noun and should be treated as a singular entity. Therefore, the verb "is" (singular) used.

Sir, our list of grievances here ________ a long one.

• are
• were
• is
• was
Correct Option: C  [ is ]

Remark: "list" is a singular noun, and when referring to a singular entity, the verb should also be singular.

The furniture in this room _______ made of teak.

• are
• have
• is
• No correction
Correct Option: C  [ is ]

Remark: Furniture is an uncountable noun and is not used in the plural, so furniture is a singular subject.