How do Indian parents come to know that their son or daughter is ready for marriage since they are the deciding factor for them?

Different parents have different parameters to figure out when their children are ready to get married. For most it's not when their children feel they are ready  to be married.

Most of the time, it's the neighbors and relatives [Char log] who decide it's time for the son or daughter to be married and parent's just follow through so as to avoid people talking about them/behind them. It could be triggered by closeness or even perceived closeness to a member of opposite sex. Another possible trigger could be the son's or daughter's desire to study or work abroad. In some cases it could even be a desire to see grandchildren by some elderly, on death bed relative. The risk is highest when the children are in the early stages of biological fertility cycle.
What do closeted gay men do to appear heterosexual?

They do nothing at all. If by closeted you mean gay men who are not out, I have known quite a few, and they do nothing aside from simply not stating that they are gay.Well, the one thing they will often do is have a girlfriend. I have no idea how this relationships works.Other than

How much should I tip in Hong Kong?

Unlike in the US, tipping is not a big issue in HK. It is neither customary nor offensive (like in Japan). But of course a tip would always be welcome. It is really a personal thing. If you're happy with the service,

How does a female over 50 lose weight?

I love seeing questions like this. How does X lose weight. What's the best workout for X. How does X lose # of weight in # of weeks.It's easy to think we are a variable and that there are inherent differences, when in truth we are more