Linq query geting list by comparing Id with an list of objects that have ids

I have the following code:

var translations = _context.Translations
       Where(t => t.LineId == lines.Id)

I got a variable named lines which is of type List<Line> every Line object has Line.Id

Now I have another table named Translations I would like to get all Translations which have Line.Id that is equal to every Line.Id from the lines list.

How can I accomplish this in a single LINQ expression?

I need something like this:

 var translations = new List<Translation>();

 foreach (var line in lines)
 {
    var translation =
    _context.Translations.FirstOrDefault(t => t.LineId == line.Id);
    translations.Add(translation);
 }

>Solution :

Project an IEnumerable<T> of your Line.Id property, then use the result in your query with the Contains method:

var lineIDs = lines.Select(l => l.Id).ToArray();

var translations = _context.Translations
    .Where(t => lineIDs.Contains(t.LineId))
    .ToList();