question: if you want to convert some part of audio from the ogm file, drag the slide bar directly, or click the play button to preview the media file, set the start time and the end time. at last, click the convert button to start to convert ogm to mp3.
Capitalize this past sentence correctly.
A: If you want to convert some part of audio from the ogm file, drag the slide bar directly, or click the Play button to preview the media file, set the Start Time and the End Time. At last, click the convert button to start to convert ogm to mp3.

question: when you book you will not be asked to send money: the credit card will only be used for guaranteeing your booking.
Capitalize this past sentence correctly.
A: When you book you will not be asked to send money: the credit card will only be used for guaranteeing your booking.

question: this helps the world wide web community because as website owners we'll receive less spam.
Capitalize this past sentence correctly.
A: This helps the world wide web community because as website owners we'll receive less spam.