I think we should sell it because the current price is very high, so the price may go down. so don't expect a big profit

The prices are still going up and although there are some hiccups selling right now is not the best option. That is my take on the question though, it is pretty subjective as we have different lives and our condition of living is almost unique to our country's. For me, holding for the long term is the best course of action.
Holding for the future is what most been targetting but as mentioned that conditions in each everyones lives are different where there are situations where you do need to make profit to sustain
or support your living in a short time manner which means dealing with the market actively is a must for you to have chance neither you do gain or loss in a short span of time that means
your capability of doing trades will really be tested out. Selling or buying then it all goes to a certain investor, if you do go for long term holds then go ahead but if you do go
with active trades then go ahead, it doesnt matter which one as long it would really make you contented and comfortable on what you are doing.