我的视图文件是

@extends('layouts.loginlayout')

@section('content')

    @if (session('status'))
        <div class="alert alert-success">
            {!! session('status') !!}
        </div>
    @endif

    @if (count($errors) > 0)
        <div class="alert alert-danger">
            <strong>Whoops!</strong> There were some problems with your input.<br><br>
            <ul>
                @foreach ($errors->all() as $error)
                    <li>{!! $error !!}</li>
                @endforeach
            </ul>
        </div>
    @endif 
//this is line 21
    {!! Form:open() !!}
        <div class="form-group">
            {!! Form::label('email','Email:') !!}
            {!! Form::text('email',null,['class'=>'form-control','id'=>'email']) !!}
        </div>

        {!! Form::submit('Login',['class'=>'btn pull-right default-button']) !!}


    {!! Form:close() !!}

@endsection