Question

the children must never touch the electric switch .( start with under no circumstance)
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Answer 1

The sentence starting with 'under no circumstances' is:

Under no circumstances should the children touch the electric switch.

• The phrase 'Under no circumstances' is used to stress something that should never be done or allowed to happen.

It is therefore used in a negative sense.

• In this case, the word 'must' has been changed to 'should' in the new form.

The phrase is directly followed by a modal verb.

Other examples are:

1. You must not lend him any money.

Under no circumstances should you lend him any money.

2. You must not surrender.

Under no circumstances should you surrender.