I am doing the [Express crash course](https://www.youtube.com/watch?v=L72fhGm1tfE), and my first clue that something was wrong is when I ran 

```
app.listen(PORT, () => console.log('Server started on port ${PORT}'));  

```

and it didn't pass the port number through. the problem persists in this area where it simply crashes the server: 

```
const logger = (req, res, next) =>{
console.log('${req.protocol}://${req.get('host')}${req.originalUrl}');
next();
};

```

Altogether now, here is the full index.js: 

```
const express = require('express');
const path = require('path');
const members = require('./Members');
const app = express();

const logger = (req, res, next) =>{
console.log('${req.protocol}://${req.get('host')}${req.originalUrl}');
next();
};

app.use(logger);

app.get('/api/members', (req, res)=> {
res.json(members);

});

app.use(express.static(path.join(__dirname, 'public')));

const PORT = process.env.PORT || 5000;

app.listen(PORT, () => console.log('Server started on port ${PORT}')); 

```

The error:

```
   console.log('${req.protocol}://${req.get('host')}${req.originalUrl}');
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    SyntaxError: missing ) after argument list
        at Module._compile (internal/modules/cjs/loader.js:723:23)
        at Object.Module._extensions..js (internal/modules/cjs/loader.js:789:10)
        at Module.load (internal/modules/cjs/loader.js:653:32)
        at tryModuleLoad (internal/modules/cjs/loader.js:593:12)
        at Function.Module._load (internal/modules/cjs/loader.js:585:3)
        at Function.Module.runMain (internal/modules/cjs/loader.js:831:12)
        at startup (internal/bootstrap/node.js:283:19)
        at bootstrapNodeJSCore (internal/bootstrap/node.js:622:3)

```