about 3 months, there has been a lot of fluctuation causing the price of ETH to drop dramatically. At this time Should hold ETH ? Can ETH price increase again 1k3$ again in late 2018 ? 
Yes, there is such a hope. Ethereum can quite reach and its former price record in 1400 dollars. However, one should bear in mind that this coin is like! other types of crypto-currencies, in price termssims from bitcoin. Therefore, if bitcoin also rises to its previous level of $ 20,000 by the end of the year, ethereum will easily do so.
In addition, if the Plasma project is implemented in ethereum, which will increase the possibility of scaling this coin to hundreds of thousands of transactions per second, the price for ethereum will increase very sharply.