The use of tugs towing on a line is used most often when con...

The use of tugs towing on a line is used most often when conventional tugs are assisting vessels. The advantage of this method is that it can be used in ________ waters. The forward tugs, sometimes, has two towlines so called __________ lines.
According to Capt. Henk Hensen, in the book “Tug Use in Port”, which answer best fill in the blanks?