Sentence improvement — choose the best correction for the clause of condition: rewrite ‘‘I shall not go untill I am invited’’ using a natural, concise conditional structure that avoids a double negative and fixes the spelling, e.g., ‘‘Unless I am invited, I shall not go.’’

Given data

• Original sentence: I shall not go untill I am invited.
• Target: Select the best improvement.

Concept/Approach
English often prefers the conjunction unless to express a negative condition. Instead of a clumsy 'not … until' with a negative main clause, we can recast the idea as 'Unless … , …' which is concise and idiomatic.Also, correct the spelling: until, not untill.

Option analysis
Unless I am invited — Best: 'Unless' replaces 'not … until', yielding a clean, standard conditional.'till I am invited' — Removes the negative but does not match the intended refusal unless meaning; it would require reshaping the main clause.'if not I am invited' — Ungrammatical word order; should be 'if I am not invited'.'No improvement' — Leaves an awkward double-negative style and a spelling error.

Step-by-step improvement
Rewrite: 'I shall not go until I am invited' → 'Unless I am invited, I shall not go.'

Common pitfalls
Confusing 'until' with 'unless', and the misspelling 'untill'.

Final Answer
Unless I am invited