字数不够，即在规定时间内（40分钟）没有达到文章字数要求（至少250单词）。对于字数不足250单词的文章，考官将会直接扣分，低于240单词扣一分，低于200单词扣两分。因此我们可以从剑桥系列范文中发现，字数不足的文章最高将不会超过5.5分。（《剑8》Test 2和《剑7》Test 4提供的考生答卷中均有体现。）
　　专家经过对多位考生的文章进行分析和总结后发现，产生该问题的原因主要有：1. 观点数量少；2. 不知道观点如何展开；3. 写作速度太慢。那么，要在规定时间内满足字数要求，考生需要想出足够多的观点；学习如何展开观点；熟练运用复杂句并提高写作速度。如何做到这几点呢，笔者将在本文中为各位考生提出几点建议。
　　建议一：“量变”引起“质变”
　　首先，考生需要想出足够多的观点。为此，很多考生会搜集各种网站所做的“写作预测”，从而提前准备观点。需要提醒考生的是不要盲目相信各种“预测”，预测题目可以练习使用，但目的是更好地提升写作水平；相反，若把所有精力集中在预测题目上，并背诵相关内容，最终很有可能会被当作模板处理，而对于使用模板或者是含有大量语言记忆片段的文章，文章最高分数不会超过5分。所以，建议考生积累观点要走“正道”，即：1. 扩大阅读面。阅读中文相关内容也可以有效地增加考生的背景知识。2. 积累同类话题的通用观点。在文章总字数要求不变的情况下，每个段落观点数量越多，意味着支持句的数量就可以相应地减少。如果一个段落中含有两个观点，那么每个观点句展开一个支持句就满足字数要求了。
　　例一：Charity organizations should give aid to people in the greatest need, wherever they are from, or help people in their own countries. Discuss both views and give your opinion. （2010年1月9日 A类）
　　Opponents of charity organizations only giving aid domestically, however, contend the assistance should be open to people in need no matter where they are from. To start with, it is the functionality of charity organizations to render help to those who are in great need, regardless of their nationalities. Otherwise, it may be considered as going breach of the purposes they are established for. What is more, not only can international charity assistance enhance the friendship of two nations, but also help eliminate the conflicts and misunderstandings, thereby stimulating the cultural exchanges between countries. （94 words）
　　上文范例段落中一共出现了3个观点句，各支持句尚未进行展开就已经有将近100单词。但是如果一个段落只有一个观点，在保持段落字数不变的情况下，支持句的数量就要相应地增加。
　　例二：Some people think that foreign tourists abroad should be charged more than local people to visit a country’s cultural and historical attractions. To what extent do you agree or disagree? （2011年4月30日 A类）
　　The reason that I oppose to the above view is the unfairness and inequality this proposal may conduce to. As is known to all, historic attractions are owned by all human beings and should be shared by people from all over the world equally and without discrimination. Once this proposal being implemented, an unfavorable impression of this country would be formed in no time. There is a fear that foreign travelers may never come again. Neither do their friends nor those who gain this negative information. And this will inevitably lead to a vicious circle. （95 words）
　　上文范例段落中只给出了一个观点句，为了满足段落内容的充实性，在这个观点句后进行了5句话的论证，字数才接近100单词。因此，在观点较少的情况下，能否将观点充分地展开成为满足字数要求的关键所在，而这对逻辑能力较弱的考生而言则会成为一大难点。
　　建议二：活用论证方法
　　如果考生对于某一主题想不出多种观点进行支持，那么，也可以通过使用议论文中常见的论证方法来进行字数的扩充。如何展开一个观点，关键在于是否能够灵活运用论证方式。常用的论证方式包括：解释（explanation），延伸（extension），举例（exemplification）和对比（contrast）等，如：
　　A lot of innovations are made with the aim of making money for a few. This is because it is the rich and powerful people in our society who are able to impose changes （such as in working conditions or property developments） that are in their own interests. （第二句为解释论证）（《剑6》Test 4）
　　My view is that young people should be encouraged to broaden their horizons. That is the best way for them to get a clear perspective of what they are hoping to do with their lives and why. （第二句为延伸论证）（《剑5》Test 2）
　　To do this, we need to improve the choice of public transport services available to travelers. For example, if sufficient sky train and underground train systems were built and effectively maintained in our major cities, then traffic on the roads would be dramatically reduced.（第二句为举例论证）（《剑8》Test 3）