Certainty & Doubt
How sure are you? In B2 speaking, you need specific phrases to show exactly how confident you are about a fact.
100% Certain 💯
80% Probable 📈
50% Uncertain 🤷
0% - Doubt 🚫
"Must be" vs "Can't be"
"His car is outside. He MUST BE home."
"His car is gone. He MUSTN'T BE home." ❌
"His car is gone. He CAN'T BE home." ✅
Quick Check ⚡
Mission 🎯
Mission 🎯
Mission 🎯
Mission 🎯
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Recent Questions
It's a great phrase for IELTS Speaking Part 3! It shows strong conviction and is perfectly acceptable. Just don't overuse it—mix it up with "It's undeniable that..." to show your vocabulary range. 💯
Why can't I use "Mustn't be" when I'm sure something is false?
Because "Mustn't" is strictly used for PROHIBITION (ការហាមឃាត់). E.g., "You mustn't smoke here." If you are using logic to deduce something is impossible, the rule in English is to use "Can't be". It's a tricky trap many B2 students fall into! 🛑
Is "Chances are" followed by a full sentence?
Yes! You use it just like "Probably".
"Chances are, [Subject + Verb]." E.g., "Chances are, it will rain." 🌧️
Is "I'm positive" informal? Can I use it in IELTS?