1, One of your classmate is not good at speaking what can you advise her to do for improving?

2. Deal with your biases

We often think from only our own perspective to deal with problems. However, it helps with critical thinking and decision making if you try thinking from someone else's point of view. Furthermore, it gives you a clearer picture of the overall situation. Let's say you're looking to solve a problem at work. Think of how your best friend might approach it, or how your partner or a sibling might. Now think of how your boss might approach it. By allowing yourself to consider different perspectives you might find yourself hitting upon solutions you hadn't previously considered.

3. Do your research

I'm sure you've heard that knowledge is power. However, many of us tend to rely a lot on what we already know and are reluctant to let go of our own beliefs.
Critical thinking requires you to let go of your beliefs sometimes to solve problems.
Reluctance to learn, research or acquire new beliefs will only hold you back and certainly won't help you with critical thinking.
By taking time to do your research and focus on learning you'll find that over time you will evolve and adapt to overcome new situations , also improve your critical thinking.

4. 4.Don’t Believe Everything You’re Told

The main step to critical thinking is to consider more than one point of view. It’s important to go beyond trusting what you hear or read as the truth, because everyone has their own opinions, motives, and biases – even academics. When learning, you should ask what evidence the source has to support their argument. Consider if there may be other possible solutions or methods. Evaluate every side to the story or problem and the strengths and weaknesses of these arguments to make an informed decision

5. Become more self-aware

Becoming more self-aware means considering your thought process, values, morals, ethics and other beliefs. What do you believe in? How do your thoughts reflect these values? Think objectively about your likes and dislikes. Knowing what you personal preferences, strengths/weaknesses and biases are can help you better understand why you approach specific situations from a certain perspective.