I must do this. (Negative)
I cannot but doing this,
I cannot help do this.
I must not do this.
I cannot help doing this.
সঠিক উত্তর:
I cannot help doing this.
ব্যাখ্যা ও নোট:
হ্যাঁ বোধক বাক্যে 'Must' থাকলে Negative এ 'cannot help + (verb+ing)' অথবা 'cannot but + V1' বসে।