nested loop wordpress without duplicate post

I want to loop which will show total 16 diffirence posts,it will divide to 4x.The seconds x4 loop will show 1 post each , total 4 posts in 1. Post not duplicate! Plz help me ty!

<div class="slide-start fl col-lg-12 clear">
    <!-- start 1st loop here, big loop to get totals 16 posts -->
        <div class="groupitem">
            <!-- start 2nd loop here to get 4 posts -->
            <div class="g-item fl">
                <a class="fl clear col-lg-12 pro-img" href=""><?php the_post_thumbnail('medium');?></a>
                <a class="fl clear col-lg-12 pro-tit" href=""><?php the_title() ;?></a>
                <span class="fl clear col-lg-12 pro-type">Hair</span>
                <p class="fl clear col-lg-12 pro-price"><span>105</span> USD <span>(0.5</span> KG)</p>
            </div>
        </div>
</div>