This is what appears from the attached code:

The code is

    <strong>Which package to register for?</strong>
    <?php
            RadioList::create(array(
                "name"=>"radioList",
                "data"=>[
                    "Pharma Research Study Toolkit"=>"1",
                    "Software Research Study Toolkit"=>"2",
                     ],
            ));

    ?>
<br>
    <div class="row">
        <div class="col-md-6 form-group">
            <strong>Name:</strong>
            <?php TextBox::create(array(
                "name"=>"Name",
                "attributes"=>array(
                    "class"=>"form-control",
                    "placeholder"=>"full name",
                )
            )
            );?>
        </div>
        <div class="col-md-6 form-group">
            <strong>email:</strong>
            <?php TextBox::create(array(
                    "name"=>"email",
                    "attributes"=>array(
                        "class"=>"form-control",
                        "placeholder"=>"email address",
                    )
                )
            );?>
        </div>
        <div class="col-md-6 form-group">
            <strong>company:</strong>
            <?php TextBox::create(array(
                    "name"=>"email",
                    "attributes"=>array(
                        "class"=>"form-control",
                        "placeholder"=>"company",
                    )
                )
            );?>
        </div>
        <div class="col-md-6 form-group">
            <strong>email address to use for access:</strong>
            <?php TextBox::create(array(
                    "name"=>"email",
                    "attributes"=>array(
                        "class"=>"form-control",
                        "placeholder"=>"email address",
                    )
                )
            );?>
        </div>

I'd like all the text boxes to line up vertically (rather than in two columns). What am I doing wrong?