Syllogisms-Which are valid? Correct the invalid ones.

Question

Brain Surgeons save lives.
Marie is a brain surgeon.
Therefore, Marie saves lives.

An English Bulldog is a dog.
All dogs have four legs.
Therefore, English Bulldogs have four legs.

All humans grow.
All children are human.
Therefore, children grow.

I love chocolate.
All brownies are made of chocolate.
Therefore, I love brownies.

Shirts are composed of threads.
Threads are made from cotton.
Therefore, shirts are composed of threads.

Jack is very talented.
Talented people are successful in life.
Therefore, Jack is successful in life.

Kids are energetic.
Susan is energetic.
Therefore, Susan is a kid.

All computers need electricity.
The Dell 500 is a computer.
Therefore, the Dell 500 needs electricity.

Mrs. Shaffer wears glasses that prohibit her from seeing any humans.
She is able to see Mr. Shaffer.
Therefore, Mr. Shaffer is not human.

Students who want to make good grades study.
Michelle studies.
Therefore, Michelle wants to make good grades.

All fruits have seeds.
Cantaloupe have seeds.
Therefore, cantaloupe is a fruit.

All Texans drive trucks.
Brian is a Texan.
Therefore, Brian drives a truck.

Answer 1

It looks like a few are quite wrong that you missed. Let me give you one example:

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Students who want to make good grades study.
Michelle studies.
Therefore, Michelle wants to make good grades.
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What if Michelle studies because her parents force her to?

Corrected, it would say Michelle wants good grades. Therefore, Michelle studies.

Answer 2

Brain surgeons save lives
Marie is a brain surgeon,
Therefore, Marie saves lives.

This would be correct, if the first premise would include the word"all"
All brain surgeons save lives,
Marie is a brain surgeon,
Therefore, Marie saves lives.