question: these are the words you often think when you encounter operating system crash. os crash can be disastrous because you might end up losing all files or even complete data from your hard disk.
Capitalize this past sentence correctly.
A: These are the words you often think when you encounter operating system crash. OS crash can be disastrous because you might end up losing all files or even complete data from your hard disk.

question: before you can open a wbt file, you'll need to figure out what kind of file the wbt file extension refers to.
Capitalize this past sentence correctly.
A: Before you can open a WBT file, you'll need to figure out what kind of file the WBT file extension refers to.

question: it might also be hiding in a spam email attachment.
Capitalize this past sentence correctly.
A: It might also be hiding in a spam email attachment.